Liquid level control device

ABSTRACT

A liquid level control device for controlling the flow of liquid into a reservoir, storage tank or the like, incorporating automatic shut-off characteristics. The device includes nozzle means including a fluid amplifier for automatically closing valve means in response to sensing means disposed remote from the nozzle means and fluid amplifier. The remote sensing means is responsive to the static presence of the interface at a sensing level of liquid in the reservoir.

Background Of The Invention

The present invention relates generally to liquid level control devicesand, in particular, to devices which may be utilized as nozzles tocontrol the flow of liquid into a reservoir, storage tank or the like.The device of the present invention is particularly useful in anapplication where automatic shut-off features are desirable.

In U.S. Pat. No. 3,703,907, a fluid amplifier is disclosed having aninlet and an outlet zone and adapted for use in a liquid reservoir tosense a change of liquid level therein. The amplifier is adapted to bepositioned adjacent the desired liquid sensing level in the reservoirand adapted for directing a substantially laminar power streamsubstantially transversely to the surface of the liquid in thereservoir. Inlet means is constructed and arranged such that a fluidpower jet is abruptly altered to a substantially turbulent flow patternwhen the liquid level in the reservoir rises to a sensing level. Thisabrupt alteration develops a fluid pressure signal which may be used tocontrol various apparatus.

For instance, U.S. Pat. No. 4,211,249 discloses a fluid amplifier asdescribed above in a liquid level control system for maintaining thereservoir at or near a predetermined liquid maintenance level, such asin swimming pools or the like.

Fluid amplifiers of the character described also have been used inautomatic shut-off nozzles as disclosed in U.S. Pat. No. Re. 29,715wherein a nozzle is shown particularly useful in an application such asself-service gasoline retail outlets.

There is a need for and it would be desirable to provide a liquid levelcontrol device incorporating automatic shut-off characteristics forcontrolling the flow of liquid into a reservoir such as a swimming pool,storage tank or the like, wherein the sensing level of liquid in thereservoir is at a remote point from the fluid amplifier itself. Thepresent invention is directed, in part, to satisfying such a need.

Summary Of The Invention

An object, therefore, of the present invention is to provide a liquidlevel control device for controlling the flow of liquid into areservoir, storage tank or the like, including automatic shut-offcharacteristics, and wherein the device can be located remote from theactual sensing level of liquid in the reservoir.

In the exemplary embodiment of the invention, the liquid level controldevice includes nozzle means having a liquid passage therethrough fordeveloping a substantially laminar liquid power stream. The nozzleincludes valve means in the liquid passage for opening and closing thepassage, along with manually operable valve opening means. Fluidamplifier means is disposed in the liquid power stream and isoperatively associated with the valve means for generating a positivefluid pressure to maintain the valve means open in the presence of thelaminar stream. The fluid amplifier includes an access region to theliquid power stream between an inlet and outlet of the amplifier.Sensing means in provided remote from the nozzle and in communicationwith the access region. The sensing means is responsive to the staticpresence of the interface at a sensing level of liquid in the reservoirto communicate liquid to the access region for physically contacting thesubstantially laminar power stream to alter the laminar stream to asubstantially turbulent flow pattern. This alteration disrupts thepressure generating ability of the fluid amplifier and thereby closesthe valve means in response to the remote sensing of a level of liquidin the reservoir.

The sensing means comprises conduit means, such as an open ended tube,in communication and leading from the access region to a desired remotepoint for sensing a level of liquid in the reservoir.

In the preferred embodiment the fluid amplifier means includes inletmeans for developing the substantially laminar power stream and outletmeans spaced from the inlet means. Restricting means is provided forrestricting flow of liquid at the outlet to create a negative pressurein the access region to draw liquid through the sensing means from theinterface at the sensing level of liquid in the reservoir. Therestricting means herein comprises a fitting defining a restrictiveorifice at the outlet for the passage of the power stream therethrough.

By using the restricting means for creating a negative pressure in theaccess region of the fluid amplifier, the sensing means can extend awayfrom the amplifier to a remote point for sensing the level of liquid inthe reservoir and still draw sufficient liquid from the interface at thesensing level to affect the fluid amplifier which automatically shutsoff the flow of liquid to the reservoir.

The device of the present invention, although shown herein for use infilling swimming pools or similar reservoirs, is equally applicable fora wide range of applications such as farm applications in fillinglivestock tanks as well as in industrial applications for fillingchemical tanks where it would be desirous to isolate the chemical levelsensing area and the fumes created thereby from the actual actuatingcomponents of the device and its operator.

Other objects, features and advantages of the invention will be apparentfrom the following detailed description taken in connection with theaccompanying drawings.

Description Of The Drawings

The features of this invention which are believed to be novel are setforth with particularity in the appended claims. The invention, togetherwith its objects and the advantages thereof, may be best understood byreference to the following description taken in conjunction with theaccompanying drawings, in which like reference numerals identify likeelements in the figures and in which:

FIG. 1 is a central sectional view through a liquid level control devicein the form of an automatic shut-off nozzle incorporating the remotesensing means of the present invention, with a laminar power streampassing through the device;

FIG. 2 is a view similar to that of FIG. 1, with a liquid level beingsensed and the laminar power stream altered;

FIG. 3 is a detailed longitudinal sectional view of the device of thepresent invention;

FIG. 4 is a fragmented sectional view of the access means at the inletof the fluid amplifier;

FIG. 5 is a somewhat schematic view of the device of the presentinvention located in the skimmer coverplate of an in-ground swimmingpool;

FIG. 6 is a somewhat schematic view of the device of the presentinvention located on a bracket along the edge of a swimming pool; and

FIG. 7 is a somewhat schematic view of the device of the presentinvention located in a below-ground filling system for a swimming pool.

Detailed Description Of The Invention

Referring to the drawings in greater detail, and first to FIG. 1, aliquid level control device, generally designated 10, is illustrated forcontrolling the flow of liquid into a reservoir such as a swimming pool,storage tank or the like. The device is illustrated as nozzle meansincluding a liquid passage 12 therethrough for developing asubstantially laminar liquid power stream indicated by the arrow 14. Thedevice includes a housing 16 having a coupling 18 for attachment to asupply hose, such as a common garden hose.

Valve means, generally designated 20, is provided in liquid passage 12for opening and closing the passage. The valve means includes a manuallyoperable valve opening means having a knob or handle 22 secured to adiaphragm 24. Diaphragm 24 is integral with a valve closure member 26which engages a valve seat 28 defining an entrance to liquid passage 12.A coil spring 30 is sandwiched between housing 16 and the valve closuremember to bias the closure member against valve seat 28. Valve means 20includes a second diaphragm 32 in housing 16 and separates the fluidinput portion of housing 16 from a positive pressure diaphragm chamber34. The valve closure member 26 and diaphragm 24 are connected to thesecond diaphragm 32 by means described hereinafter.

Fluid amplifier means, generally designated 36, is disposed in liquidpower stream 14 for generating a positive fluid pressure to diaphragmchamber 34 to maintain the valve means open in the presence of a laminarliquid power stream. More particularly, fluid amplifier 36 includes aconduit 38 communicating with the positive pressure diaphragm chamber34. Conduit 38 has a portion 40 extending transversely across and intothe laminar liquid power stream 14. Conduit portion 40 has a port 42exposed to the power stream for generating a positive fluid pressuresignal, through the conduit, and to diaphragm chamber 34.

Fluid amplifier means 36 has an inlet 44, an outlet 46 and an accessregion 48. It can be seen that access region 48 is of a slightly largercross section than inlet 44 so that the laminar liquid power streamfreely flows from inlet 44 to port 42.

It will be understood that as long as a laminar liquid power streamflows through amplifier 36, a pressure signal is generated intodiaphragm chamber 34 to hold valve closure member 26 open after initialmanual opening by pulling on knob 22. This is true because the pressureon diaphragm 34 is greater than the biasing force of compression coilspring 30.

The present invention contemplates sensing means remote from nozzle 10and amplifier 38, in communication with access region 48, for sensingthe level of liquid in a reservoir, storage tank or the like. Moreparticularly, an access port 50 extends through the housing transverselyof access region 48. Conduit means in the form of an open ended tube 52is in communication with and leads away from the access region to adesired point for sensing a level of liquid in the reservoir. It shouldbe noted that although tube 52 is shown of a relatively short length inFIG. 1, longer lengths are contemplated. For instance, a liquid lever 53is shown below the sensing opening 54 of tube 52 to indicate a "lowlevel" in the reservoir.

Referring to FIG. 2, sensing tube 52 is responsive to the staticpresence of the interface at a sensing level of liquid in the reservoirto communicate liquid to access region 48 for physically contacting thesubstantially laminar power stream to alter the laminar stream to asubstantially turbulent flow pattern. More particularly, it can be seenin FIG. 2 that the interface at the liquid level 53 has reached thesensing opening 54 of sensing tube 52. At this point, liquid is drawnthrough the tube into access region 48 whereby the liquid physicallycontacts the laminar power stream to effect a substantially turbulentflow pattern as indicated at 56. The entering liquid from the reservoirmay, in fact, divert the power stream, as shown, away from fluidamplifier port 42. When this occurs, the pressure signal to positivepressure diaphragm chamber 34 is reduced and compression coil spring 30causes the valve means 20 to close and shut-off the supply of liquid.

In other words, alteration of the laminar liquid power stream disruptsthe pressure generating ability of the fluid amplifier and therebycloses the valve means in response to the remote sensing of a level ofliquid in the reservoir.

In order to positively effect drawing of liquid from the reservoir atthe sensed interface level 53 thereof through sensing tube 52,restricting means 58 is provided for restricting flow of liquid at theoutlet 46. This restriction creates a negative pressure in access region48 and, in effect, sucks liquid through sensing tube 52 and intophysical contact with the power stream to disrupt the stream.

FIG. 3 is a detailed sectional view of the device of the presentinvention described functionally in relation to FIGS. 1 and 2. It can beseen that coupling 18 can comprise a standard screw connection for atypical garden hose. The means for interconnecting diaphragms 24, 32comprise one or more connecting rods 60 whereby the diaphragms areoperatively associated for conjoint movement. The diaphragms includeflexible wafers 62 secured about their edges on the inside of more rigidwashers 64 secured to the connecting rods 60. The laminar liquid powerstream is formed by a central tube 66 within an outer tube 68, withconduit means 38 between the tubes. The conduit means communicatesbetween fluid amplifier port 42 and positive pressure diaphragm chamber34. Valve closure member 26 includes a resilient cushion insert 70 forengaging valve seat 28. Lastly, restricting means 58 comprises a nozzletip which is press-fit to define a restrictive orifice 72 at the outletof the fluid amplifier.

FIG. 4 is a fragmentary view illustrating the transverse disposition ofaccess port 50 relative to access region 48.

FIGS. 5 and 6 illustrate exemplary applications of the device of thepresent invention as used for filling swimming pools. In FIG. 5, thedevice is mounted in the skimmer coverplate 74 along the edge of anin-ground swimming pool. It can be seen that sensing tube 52 extendsdownwardly to a remote position to sense the static presence of theinterface at a sensing level 76 of liquid in the skimmer channel 78 ofthe pool. FIG. 6 shows the device mounted on a bracket 80 alongside anabove-ground swimming pool, with the sensing tube 52 again extendingdownwardly to a remote level 82 of the liquid in the pool. Both FIGS. 5and 6 illustrate that the device itself need not project into the waterin the pool and, of course, sensing tube 52 may be longer than as shown.The negative pressure created by restricting means 58 (FIGS. 1-3)creates a negative pressure in access region 48 to draw liquid upwardlyinto the fluid amplifier sufficient to disrupt the laminar liquid powerstream therethrough.

Referring to FIG. 7, a somewhat schematic illustration of the use of thedevice of the present invention is illustrated as incorporated in abelow-ground filling system for a swimming pool. In this illustration,valve means 20 is disposed above ground for manual opening of the valve.A water supply conduit 84 extends from the valve downwardly to fluidamplifier 36. Positive pressure conduit 38 extends upwardly from thefluid amplifier back to valve 20 to automatically shut-off the valve asdescribed above. Like numerals are used to designate like components ofthe fluid amplifier, such as access region 48. In this application ofthe invention, sensing tube 52 extends upwardly to sense the staticpresence of the interface at a sensing level 86 of the water in thepool. Since the fluid amplifier is located below the sensing level, thewater head above the amplifier is sufficient to effect flow of waterdownwardly through tube 52 sufficient to disrupt the laminar powerstream in the amplifier. Consequently, the restricting means 58described above in relation to the above-ground filling applications isnot necessary.

Thus, it can be seen that a new and improved liquid level control devicehas been provided for controlling the flow of liquid into a reservoirsuch as a swimming pool, storage tank or the like, wherein automaticshut-off characteristics are important, while providing sensing meansfor the fluid amplifier at a point remote from the amplifier itself. Therestricting means 58 creates sufficient negative pressure in accessregion 48 to effect drawing of disrupting liquid through sensing tube 52into physical contact with the normally substantially laminar powerstream through the device and fluid amplifier. Although the device isshown herein as incorporated in swimming pool applications, it is to beunderstood that a wide range of applications are contemplated.

It will be understood that the invention may be embodied in otherspecific forms without departing from the spirit or centralcharacteristics thereof. The present examples and embodiments,therefore, are to be considered in all respects as illustrative and notrestrictive, and the invention is not to be limited to the details givenherein.

What is claimed is:
 1. A liquid level control device for controlling theflow of liquid into a reservoir, storage tank or the like,comprising:nozzle means including fluid amplifier means having inletmeans for developing a substantially laminar liquid power stream, outletmeans spaced from said inlet means, signal port means exposed to saidliquid power stream for generating a positive fluid pressure toappropriate control means supplying liquid in the presence of saidlaminar stream, and an access region to said liquid power stream;sensing means remote from said nozzle means and in communication withsaid access region, said sensing means being responsive to the staticpresence of the interface at a sensing level of liquid in said reservoirto communicate liquid to said access region for physically contactingsaid substantially laminar power stream to alter said laminar stream toa substantially turbulent flow pattern which disrupts the pressuregenerating ability of said fluid amplifier means and thereby stops thesupply of liquid in response to the remote sensing of a level of liquidin said reservoir; and restricting means for restricting flow of liquidat said outlet means to create a negative pressure in said access regionto draw liquid through said sensing means from the interface at thesensing level of liquid in said reservoir.
 2. The liquid level controldevice of claim 1 wherein said sensing means comprises conduit means incommunication with and leading from said access region to a desiredpoint for sensing a level of liquid in said reservoir.
 3. The liquidlevel control device of claim 2 wherein said conduit means comprises anopen ended tube.
 4. The liquid level control device of claim 1 whereinsaid restricting means includes a restrictive orifice at said outletmeans for the passage of said power stream therethrough.
 5. The liquidlevel control device of claim 1 wherein said sensing means comprisesconduit means in communication with and leading from said access regionto a desired point for sensing a level of liquid in said reservoir. 6.The liquid level control device of claim 5 wherein said conduit meanscomprises an open ended tube.
 7. The liquid level control device ofclaim 1 wherein said fluid amplifier means is located below the surfaceof liquid in said reservoir, and said sensing means extends upwardlytherefrom to a desired sensing level of liquid in the reservoir.
 8. Theliquid level control device of claim 7 wherein said sensing meanscomprises conduit means in communication with and leading from saidaccess region to a desired point for sensing a level of liquid in saidreservoir.
 9. A liquid level control device for controlling the flow ofliquid into a reservoir, storage tank or the like, comprising:nozzlemeans including a liquid passage therethrough for developing asubstantially laminar liquid power stream, valve means in said liquidpassage for opening and closing said passage, valve opening means, andfluid amplifier means in said liquid power stream and operativelyassociated with said valve means for generating a positive fluidpressure to maintain said valve means open in the presence of saidlaminar stream, said fluid amplifier means including an access region tosaid liquid power stream and means for creating a negative pressure insaid access region; and sensing means remote from said nozzle means andin communication with said access region, said sensing means beingresponsive to the static presence of the interface at a sensing level ofliquid in said reservoir to draw liquid to said access region under theinfluence of said negative pressure for physically contacting saidsubstantially laminar power stream to alter said laminar stream to asubstantially turbulent flow pattern which disrupts the pressuregenerating ability of said fluid amplifier means and thereby closes saidvalve means in response to the remote sensing of a level of liquid insaid reservoir.
 10. The liquid level control device of claim 9 whereinsaid sensing means comprises conduit means in communication with andleading from said access region to a desired point for sensing a levelof liquid in said reservoir.
 11. The liquid level control device ofclaim 10 wherein said conduit means comprises an open ended tube. 12.The liquid level control device of claim 9 wherein said means forcreating a negative pressure in said access region comprises restrictingmeans for restricting flow of liquid at an outlet of said fluidamplifier.
 13. The liquid level control device of claim 12 wherein saidrestricting means includes a restrictive orifice at an outlet of saidfluid amplifier means.
 14. A liquid level control device for controllingthe flow of liquid into a reservoir, storage tank or the like,comprising:nozzle means including fluid amplifier means having inletmeans for developing a substantially laminar liquid power stream, outletmeans spaced from said inlet means, means exposed to said liquid powerstream for generating a positive fluid pressure to control the supply ofliquid, an access region to said liquid power stream, and means forcreating a negative pressure in said access region; and sensing meansremote from said nozzle means and in communication with said accessregion, said sensing means being responsive to the static presence ofthe interface at a sensing level of liquid in said reservoir to drawliquid to said access region under the influence of said negativepressure for physically contacting said substantially laminar powerstream to alter said laminar stream to a substantially turbulent flowpattern which disrupts the pressure generating ability of said fluidamplifier means and thereby closes said valve means in response to theremote sensing of a level of liquid in said reservoir.
 15. The liquidlevel control device of claim 14 wherein said means for creating anegative pressure in said access region comprises restricting means forrestricting flow of liquid at an outlet of said fluid amplifier means.16. The liquid level control device of claim 15 wherein said restrictingmeans includes a restrictive orifice at an outlet of said fluidamplifier means.